Environment Variables
Add to favorites
Make environment variables secret with a .env file
React Hooks Handbook
1
Intro to React Hooks
3:39
2
Create your first React app
4:23
3
React Component
2:54
4
Styling in React
5:06
5
Styles and Props
2:22
6
Understanding Hooks
3:21
7
useState Hook
2:54
8
useEffect Hook
3:41
9
useRef Hook
3:00
10
Props
3:11
11
Conditional Rendering
4:21
12
Load Local Data
4:04
13
Fetch Data from an API
5:40
14
Toggle a state
4:05
15
useInput Hook
6:04
16
Gatsby and React
6:44
17
NextJS and React
5:24
18
React TypeScript Part 1
8:19
19
React TypeScript Part 2
7:35
20
useScrollPosition Hook
4:26
21
useOnScreen hook
8:08
22
useContext Hook
8:32
23
Fragments
2:43
24
Lazy Loading
4:05
25
React Suspense
3:13
26
Environment Variables
4:43
27
Reach Router
5:31
28
URL Params
4:04
29
SEO and Metadata
6:47
30
Favicon
3:03
31
Dynamic Favicon
2:14
32
PropTypes
3:54
33
Custom PropTypes
3:58
34
useMemo Hook
4:05
35
forwardRef Hook
3:28
36
Handling Events
5:44
37
Spread attributes
3:35
38
useMousePosition Hook
4:55
39
useReducer with useContext Part 1
7:33
40
useReducer with useContext Part 2
6:48
41
useReducer with useContext Part 3
5:43
42
Netlify
5:08
43
Gatsby Cloud
6:19
44
Gatsby Plugin Image
8:11
45
useOnClickOutside Hook
6:32
46
useWindowSize Hook
4:14
47
usePageBottom hook
4:48
48
useLocalStorage Hook
5:27
49
Three.js in React Part 1
17:33
50
Three.js in React Part 2
11:18
Why keep my keys private?
A study from the North Carolina State University found that thousands of sensitive information, including API keys, are leaked every day on Github. It's bad practice to hard-code your private keys in your project, as hackers can steal them, use them and, eventually, maximize your number of requests quota. In some extreme cases, if the API is linked to your credit card, and the hackers go over your quota, your credit card can be charged.
Create the .env file
To solve this potential issue, avoid hard-coding keys in your project and store them in a .env file. Create a new file, called .env, at the root level of your project. This is where we'll store all of our API keys.
Add to gitignore
Once you added the file, you'll see that the title of the file is in green, meaning that you'll still be committing this file if you commit to Github now. It's important to add it to your .gitignore file, to tell Github to ignore this file when committing.
Once you add .env to the .gitignore file, you'll see that the .env file's title becomes grey, meaning that Github will ignore it.
Add your environment variables
In the newly created .env file, add all your environment variables. Here's an example of how you should add them:
MY_API_KEY=1234567abcdefBy default, all environment variables are only available in NodeJS, to prevent exposing sensitive information to hackers. If you wish to expose your environment variables to the browser, for example an API URL that isn't really secret, you'll need to prefix each key with a few words, depending on the platform you're using:
- REACTAPP for a create-react-app-application;
- GATSBY_ for a Gatsby application;
- NEXTPUBLIC for a NextJS application;
For example, for a create-react-app application, I'll save the following not secret code in my .env file, to expose it to the browser (and be able to call it from my frontend):
REACT_APP_NOT_SECRET_KEY=1234567abcdefAccess your environment variables
You might need to restart your server when you change something in your .env file to see the changes reflected. You can access your environment variables that are exposed to the browser with:
process.env.REACT_APP_NOT_SECRET_KEYPlease note that environment variables without a prefix won't be accessible from the browser. They'll return undefined.
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react-hooks-handbook-environment-variables
1
Intro to React Hooks
An overview of React Hooks and the frameworks you can use to build your React application blazingly fast
3:39
2
Create your first React app
Create your first React project from the Terminal and save it on your local computer
4:23
3
React Component
Create your first JSX component using React
2:54
4
Styling in React
How to style your React components using inline styling, separate stylesheets or styled-components
5:06
5
Styles and Props
Render different styles depending on different properties passed to your component
2:22
6
Understanding Hooks
Learn about the basics of React Hooks, which introduced at React Conf 2018
3:21
7
useState Hook
Use the useState hook to manage local state in your React component
2:54
8
useEffect Hook
Manage with your component's lifecycle with the useEffect hook
3:41
9
useRef Hook
Learn about the useRef hook, which replaces the JavaScript getElementById way
3:00
10
Props
Learn about props in React to pass data from parent to child components
3:11
11
Conditional Rendering
Render different UIs depending on different conditions and states
4:21
12
Load Local Data
Load local JSON data into your React application
4:04
13
Fetch Data from an API
Learn the basics of asynchronous functions and promises by fetching data from an API using fetch, useEffect and useState
5:40
14
Toggle a state
Learn how to toggle a state from true to false and back again
4:05
15
useInput Hook
Create a hook to get the value and the onChange event of input fields
6:04
16
Gatsby and React
Create a static content-oriented website using React on Gatsby
6:44
17
NextJS and React
Create your first NextJS React application
5:24
18
React TypeScript Part 1
Learn how to create a React TypeScript application using the Create React App, Gatsby and NextJS methods
8:19
19
React TypeScript Part 2
Learn the basics of TypeScript and how to use TypeScript in a React component
7:35
20
useScrollPosition Hook
Create a custom hook to listen to the current window position of the user
4:26
21
useOnScreen hook
Create a custom hook to listen to when an element is visible on screen
8:08
22
useContext Hook
Manage global states throughout the entire application
8:32
23
Fragments
Group multiple children together with React Fragments
2:43
24
Lazy Loading
Lazy Load heavy components to improve performance
4:05
25
React Suspense
Wait for data with React Suspense and React.lazy
3:13
26
Environment Variables
Make environment variables secret with a .env file
4:43
27
Reach Router
Create a multiple-pages React application with Reach Router
5:31
28
URL Params
Create unique URL with URL Params
4:04
29
SEO and Metadata
Optimize a React application for search engines with React Helmet
6:47
30
Favicon
Add an icon to a React website
3:03
31
Dynamic Favicon
Change the favicon's fill color depending on the user's system appearance
2:14
32
PropTypes
Implement props type-checking with PropTypes
3:54
33
Custom PropTypes
Create a custom PropType using a validator function
3:58
34
useMemo Hook
Prevent unnecessary re-renders when the component stays the same
4:05
35
forwardRef Hook
Forward a ref to a child component
3:28
36
Handling Events
How to handle events in React
5:44
37
Spread attributes
Learn how to make use of the spread operator
3:35
38
useMousePosition Hook
Detect the user's mouse position on a bound element
4:55
39
useReducer with useContext Part 1
Create a reducer to be used in a context
7:33
40
useReducer with useContext Part 2
Incorporate useReducer with useContext
6:48
41
useReducer with useContext Part 3
Connect the context and reducer with the frontend
5:43
42
Netlify
Deploy to production using Netlify
5:08
43
Gatsby Cloud
Deploy to production using Gatsby Cloud
6:19
44
Gatsby Plugin Image
Use gatsby-plugin-image for automatic image resizing, formatting, and higher performance
8:11
45
useOnClickOutside Hook
Toggle a modal visibility with a useOnClickOutside hook
6:32
46
useWindowSize Hook
Create a hook to determine the width and height of the window
4:14
47
usePageBottom hook
Detect if the user scrolled to the bottom of the page
4:48
48
useLocalStorage Hook
Store an item in a browser's local storage
5:27
49
Three.js in React Part 1
Bring your website to life with beautiful 3D objects
17:33
50
Three.js in React Part 2
Bring your website to life with beautiful 3D objects
11:18
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